Congress should block proposed changes to rules governing U.S. law enforcement investigations, tech groups say. The changes would allow judges to issue warrants for hacking and surveillance in cases where investigators don’t know the target computer’s location. A coalition of 50 tech trade groups, digital rights groups, and tech companies signed a letter to Congress. The change could hurt network security efforts, the groups said in a letter sent Tuesday. The Supreme Court approved changes to Rule 41 of the Federal Rule of Criminal Procedure in April.”]